Furnace



(5. M. CROSSEN.

FURNACE. APPLICATION FILED MAY 9, 1921 Patented Nov. 21, 1922.

3 SHEETS-SHEET I.

my? Wa er Geoye/Z Crease.

G. M. CROSSEN.

FURNACE. I I APPLICATION FILED MAY 9, 1921. 1,436,437, Patented Nov. 21,1922..

3 SHEETS-SHEET 2.

4" W FEE Patented Nov. 21,1922.

.UNITED STATES PATENT OFFICE.

ononen 1a. cnossnu, or MINNEAPOLIS, ivi'ruivnsora, assmuou or THIRTY bunnun'nnnnrrrs r0 LLOYD n. JG'NES AND TI-HRT'Y oun-nuunannrnsro HENRYLYONS.

FURNACE.

Application filed May'l), 1921. Serial No. 468,075.

T 0 all whom it may concern:

Be it known that I, Gnonen M. Cnossnx, a citizen. of the United States,residing at Minneapolis, in the county of Hennepin and State ofhflinnesota, have invented certain new and useful Improvements inFurnaces; and I do hereby declare the following to be a full, clear,.andexact description of the invention, such as will enable others skilledin the art to which it appertains to make and use the same.

My invention relates to furnaces and, more particularly, to an improvedgrate structure and certain other cooperating devices, and has for itsobject to improve the same, as will hereinafter appear.

To the above end, generally stated, the invention consists of the noveldevices and combinations of devices hereinafter dcscribed and defined inthe claims. 7

In the accompanying drawings, which illustrate the invention, likecharacters indicate like parts throughout the several views.

ieferring to the drawings: 1 i

Fig. 1 is a plan view of the improved turnace with some parts removedand other parts broken away in section;

Fig. 2 is a front elevation;

Fig. 3 is a view principally in transverse vertical section, takensubstantially on the irregular line 3-;) of Fig. 1;

Fig. l is a view in longitudinal central section taken on the line 4.--lof Fig. 1;

Fig. 5 is a fragmentary detail view of the grate bars and shakingmechanism therefor, with some parts in section substantially on the line5--5 of Fig. l; c

F 6 is a view inside'elevation of the stoker conveying trough;

Fig. '7 is a perspective view otone oi the grate bar extensionsorrimsections; and i Fig. 8 is a perspective view of one of the jointplates. y i

The masonry portion of the improved 't'urnace includesa base 9, frontwall 10, side walls 11, top l2 and back or bridge wall 1.3, having aflame andsmoke passageway 14:,

which leads to the flues ot' a steam boiler, not

shown. At the .front of the furnace is an ash pit 15 formed in the base9. The front wall lOis covered by a metallic door plate 16 having upperand lower pairs of door openlugs normally closed by hinged doors 17 and18, respectively, the former of which open into the furnace above agrate structure and the latter of which open into the furnace below saidgrate structure. i

The grate structure is of annular formation and mounted to revolve on avertical axis and includes a grate center 19, a sectional. grate rim 20and radially disposed grate bars 21, located between said grate centerand grate rim and mounted for rocking movement. A skeleton frame isprovided to carry the grate center, grate rim and grate bars andincludes concentric rings and 22 secured to radial arms 23 carried by ahub 24: rotatably mounted on a pintle 25 secured to the base 9. Thegrate center 19 closes the space within the inner frame rin 22 and isremovably supported on bracket 26 secured tosaid ring. I

The radial grate bars 21 are rockably mounted onthe two rings 22 byprovidii'ig the "inner ends thereof withatrunnion 27 mounted in bores orseats in the inner ring 22' and by providing the outer ends of saidgrate bars with yoke-like seats 28 which straddle pintles 29 secured toand projecting radially inward from the outer frame ring 22. To look thegrate bars 21 in position, keys or cotter pins 30 are passed'throug hthe seats 28 below the'pintles 29. It will be noted that the inner endsof the upper surfaces of the grate bars 2l-are extended, at 3i, over theinnertrame ring 22', and ,teri'niuate close to the pl-iriphery of thegrate center 19.

The grate rim sections20 provide extensions of thegrate surface andareremovably supported on the upperedge oi the outer frame rim 22-, byforming on the under surfaces thereof depending radially spaced flangesor lugs which eml ace said rim and hold saidsections against radialmovement thereon. Said grate rim sections 20 are held on the outer ring22 against circumteu ential movement, and in alignment with the gratebars'21 by forming, in the inner lugs 2:52 thereof, notches '33 toreceive the pintles 2-9.

The under surfaces of the rim sections 20,

36 laid in the masonry walls 10, 11 and 13. These joint plates areremovably supported on the ledge 35 by forming on. the upper edgesthereof depending flanges 37 which interlock with an annular shoulderedgroove 38 in the ring 36 at the junction of said ledge therewith. Itwill be noted that the outer edges of'the joint plates 34 and theflanges 37 extend into the masonry walls andentirely close the jointbetween said walls and the grate rim sections 20. Obviously, an ashesfalling on the joint plates 34 will be scraped therefrom by the graterim sections 20 and be precipitated onto the base 9, during the rotationof the grate.

The grate bars 21 are connected in groups of four, by tie bars 39,pivoted at 40 to depending lugs 41 on the outer ends of said grate bars.Each tie bar 39 is independently and intermittently oscillated to rockthe respective group of grate bars 21 by a disk 42 having a crank pin4%.) connected by a link 44 to one of the pivotal connections 40 of therespective group ofgrate bars 21. The disks 42 are secured to the innerends of short shafts journaled in the outer ring 22 and have keyed totheir outer ends gears 46. The gears 46 are circumferentially spaced andarranged to successively engage a segmental rack 47 during the rotationof the grate and be rotated thereby. This segmental rack 47 is carriedby a swinging arm 48 pivoted to a bracket 49 secured to the base 9. andis of such length as to give each gear 46 one complete rotation whilepassing thereover. By means of the arm 48, the rack 47 may be moved froma position where it will be engaged by the gears 46 and rock the gratebars 21 to an inoperative position where said gears will pass therebywithout rocking saidgrate bars. To accomplish this movement of the rack47 to and from operative position. there is provided ahandpiece-equipped operating bar 50, which is pivoted to said arm andworks through the door plate 1.6. It is important to note that when thegrate bars 21 are in upright or normal positions, the pivotalconnections 40, for the links 44, the crank pins43 and the shafts 4-5are on dead centers, thus holding the grate bars in said positions.

in addition to the pintle 25, the grate frame is further supported by aplurality of gears 51. which mesh with an annular rack 52 on. the loweredge of the outer frame ring 22. Said gears 51. except the one at thefront of the furnace. areidle and loosely journaled on pintle-equippedbrackets 53 secured to said base. The gear 51, at the front of thefurnace, which is driven, is secured to the inner end of the shaft 54journaled in a bearing bracket 55 secured to the base 9 and in a bearing56 in the door plate 16. ()n the outer end of the shaft 54 is a gear 57which meshes with a pinion 58 on the lower end of a vertical shaft 59journaled in bearings on a bracket 60 secured to the door plate 16. Theshaft 59 is driven by a horizontal.countershaft 61, which is connectedthereto by a beveled gear 62 and has, on its outer end, apulley 63 overwhich runs a driving belt, not shown.

It will be noted that the rocking of the grate bars 21, to shake theashes therefrom, caused by the gears 46 passing over the rack segment47, takes place over the ash pit 15. Any ashes precipitated on the base9, outside of the ash pit 15, are scraped into said pit, during therotation of the grate structure, by ascraper blade 64 suspended from oneof the frame arms 23 by means of hooks 65 on the upper edge thereof.

In connection with the improved I grate structure, I provide aco-operating stoker which includes a hopper 66 that extends from thedoor plate 16 radially over the grate structure to substantially thecenter thereof. The front end of the hopper 66 is supported on a bracket67 secured to the inner face of the door plate 16. The lower portion ofthe side walls of the hopper 66 are made in detachable sections, so thatin case they burn out, they may be removed and new ones substitutedtherefor. To protect that portion of the hopper 66 which extends belowthe arch or top 12 from heat, the lower longitudinal edges of saidhopper are provided with outstanding flanges 68 on which are supported,fire tile or brick 69.

Extending longitudinally through: the hopper 66 is a feed trough 7 0having a spiral edge 71 over which fuel is discharged onto theunderlying grate bars 21. Mounted in the feed trough 70 is a spiralconveyor 72, the shaft 73 of which is ournaled in one end in a bearingon a bracket 74, attached to the outer face of the door plate 16, and atits other end in a bearing formed in the inner end wall of the hopper66. The upper end of the shaft is also ournaled in a bearing on thebracket 74. To raise or lower the spiral feed edge 71 so as to varythe'distribution of fuel radially onto the grate bars 21, the feed trough72- is mounted on the shaft 73 for turning movement on its longitudinalaxis. Attached to the head or the outer end of the feed trough 7 (l, isahand lever 75 by which said feed trough may be turned on itslongitudinal axis to adjust the spiral feed edge 71. As shown, the handlever 75 is fulcrumed on. the shaft 73 and rigidly secured at its shortend to the head of the feed trough 70. Obviously, by manipulat ing thehand lever 7 the feed trough-7O may be turned on its axis to raise orlower the spiral feed edge 71.. It is thought that fric' tion will holdthe feed trough 70 where set but if found necessary, any suitable meansmay be provided for securing said feed trough in different adjustments.The hopper 66 is provided with a feed throat 7 6 into which fuel isdelivered and thereby conveyed into, the receiving end of the feedtrough 70. t I

The spiral. conveyor 72 is driven from the shaft 59 by a short shaft 77journaled in bracket 74- and is com'iected to said shaft 59 by avariable speed mechanism of any well known or standard construction, andindi (rated, as an entirety, by the numeral 78. The shaft 77 isconnected to the shaft 73 by a pinion 79 which meshes with a gear 80 onsaid shaft 73.

During the rotation of the grate structure, fuel is spreadcircumferentially and radially thereon by the stoker, and the prodnetsof incomplete combustion, at the front of the furnace, during theirtravel through the smoke and flame passageway 1a are re quired to passover the hot flames at the rear of the furnace and a further supply offresh air which completes the combustion, thus eliminating smoke and awaste of fuel. Just before new fuel is delivered onto the gratestructurefrom the stoker, the groups ofgrate bars are automatically andsuccessively shaken at the time the gears l6 pass over the segmentalrack 47 to remove the ashes therefrom. In case it is not desirable toremove the ashes from the grate, the rack l? may be moved intoinoperative position.

\Vhat I claim is:

1. In a furnace, the combination with a revoluble grate frame and meansfor rotating the same, of radially disposed grate bars rockably mountedon said frame, connections includin circumferentially spaced gears andcranks for rocking the grate bars, said connections being arranged tonormally lock the grate bars against rocking movement, and a rack withwhich said gears intermittently mesh during the rotation of the grateframe to rock the grate bars.

2. In a furnace, the combination with a revoluble grate frame and meansfor rotating the same, of radially disposed grate bars rockably mountedon said frame, connections including cireumferentially spaced gears andcranks for rocking the grate bars, said con-- nections being arranged tonormally lock the grate bars against rocking movement, a rack with whichsaid gears intermittently mesh during the rotation of the grate frame torock the grate bars, and means for moving the rack to and from aposition in which it will be engaged by said gears. I

3. In a furnace, the combination with an annular grate frame rotatablymounted on. an axial pivot and having an annular rack, of a plurality ofcircumferentially spaced gears which mesh with said rack, means fordriving one of said gears, radially disposed grate bars rockably mountedon the grate frame, connections including air-- cumferentially spacedgears and cranks for rocking the grate: bars, said connections beingarranged to normally lock the grate bars against rocking movement, arack segment with whichthe gears of said connections intermittently meshduring the rotation of the grate frame to rock the grate bars, and meansfor moving the rack segment to and from a position in which it will beengaged by the gears of said connection.

a. In a furnace, the combination with a revoluble grate frameand meansforrotating the same, of radially disposed grate bars rockably mountedon said frame, tic bars pivotally connecting the grate bars in groups,circumferentially spaced gearequipped cranks for oscillating the tiebars to rock the grate bars, and a rack segment with which said gearsintermittently mesh during the rotation of the grate frame to rock thegrate bars.

In afurnace, the combination with a revoluble grate frame and means forrotating the same, of radially disposed grate bars rockably mounted onsaid frame, connections including circumferentially spaced gears andcranks forrocking the grate bars, said connections being arranged tonormally lock the grate bars against rocking movement, a pivoted armhaving a rack segment with which said gears intermittently mesh duringthe rotation of the grate frame to, rock the grate bars, and means forswinging said arm to move the rack segment to and from a position inwhich it will be engaged by said gears.

6. In a furnace, the combination with a revoluble grate frame and meansfor rotating the same, of radially disposed grate bars rockably mountedon the grate frame,

means for intermittently rocking said grate bars, and grate rim segmentssupported on the grate frame and providing extensions of the gratesurface.

7. In a furnace, the combination with a revoluble grate frame and meansforrotating the same, of radially disposed grate bars rockably mountedon the grate frame, means for intermittently rocking said grate bars,and grate rim segments independently and removably supported on thegrate frame, and providing extensions of the grate surface. 4

8. In a furnace, the combination with a revoluble grate frame includingconcentric rings and means for rotating said frame, of radially disposedgrate bars having trunnions mounted in the rings of said frame forrock-ably supporting the grate bars, means for intermittently rockingsaid grate bars, and grate rim segments straddling the outer frame ring.

9. In a furnace, the combination with a revoluble grate frame includingconcentric rings and means for rotating said frame. of

radially disposed grate bars having pintles mounted in the rings of saidframe for rock ably supporting the grate bars, means forintern'iittently rocking said grate bars, and grate rim segmentsstraddling the outer frame ring, and having interlocking engage mentwithcertain of said pintles for holding the same against circumferentialmovement of said frame ring. v

10. In afurnace, the combination witha wall structure, of a revolublegrate structure Within said wall structure and means for rotating thesame, said grate structure including radially disposed grate bars and agrate rim outward thereof, a supporting ledge carried by the wallstructure, and segmental joint plates removably supported on said ledgeand extending into the Wall structure andunder-lapping the grate rim.

11. In a furnace, the combination with a wall structure, of a revolublegrate structure within said wall structure and means for rotating thesame, said grate structure inchuling radially disposed bars and. a graterim outward thereof, and having an oblique under surface, a supportingledge carried by the i 'all structure, an d segmental oint platesremovably supported on said ledge in oblique positions and extendinginto the wall structure and underlapping the oblique surface of thegrate rim. 7

12. In a furnace, the combination with a Wall structure, of a revolublegrate structure within said wall structure and means for rotating thesame, said grate structure including radially disposed grate bars and agrate rim outward thereof, a supporting ledge carried by the wallstructure, and seg mental joint plates having separable interlockingengagement with said ledge and eX- tending into the wall structure andunderlapping the grate rim.

13. in a furnace, the combination with a revoluble grate frame includingconcentric rings and means for rotating said frame, the inner of saidrings having trunnion seats and the outer of said rings having radialpintles, of radially disposed grate bars having at their inner endstrunnions arranged to enter said trunnion seats by an endwise movementof the grate bars, said grate bars having at their outer ends yoke-likeseats adapted to straddle the trunnion on said outer ring, and keysextended through said yoke-like seats below the respective pintles.

In. testimony whereof I aiiix my signature.

enonen MI] onossnu.

